Commentary -- Court's DNA Ruling Raises Important Questions

By Des Moines Register Editorial Board

Police have long used scientific tools to identify criminal suspects, ranging from head measurements and mug shots to fingerprints. Today’s law enforcement agencies have something that’s considered unsurpassed: a person’s DNA.

A DNA test run on a bit of body tissue or body fluid collected at the crime scene can be matched with near certainty as belonging to only one individual in the world.

Of course law enforcement authorities want to collect DNA samples from criminal suspects whenever they can. But the U.S. Supreme Court on Monday said the government cannot arbitrarily take a sample of your genetic material for purposes of a criminal investigation without violating the Constitution.

Unfortunately, the court set the bar so low that the question remains whether random testing of all criminal suspects may ultimately be accepted, regardless of severity of the crime. And that raises disturbing questions about government invasion of privacy.

Iowa law allows DNA tests only on convicted offenders. The Supreme Court, however, upheld a Maryland law that allows authorities to collect DNA samples from suspects arrested — but not convicted — of burglaries and violent crimes such as murder, rape and assault. Samples are entered in a national FBI database, but only after a judge has found probable cause for criminal charges.

Justice Anthony Kennedy, writing for the court, said criminal suspects are routinely searched at booking and have a lower expectation of privacy. Kennedy likened DNA samples to fingerprints, which are routinely collected and stored in a national criminal database.

Kennedy glides over some important nuances, however, that should limit the government’s ability to collect incriminating evidence without good cause. Jail booking searches are justified to find weapons or evidence related to crimes related to the arrest. The court talks about limiting tests to “serious” offenses but does not define what that means. A DNA sample provides vastly more personal information than a fingerprint, including physical and mental health profiles.

The government needs reasonable suspicion of a suspect’s connection to a crime to justify a search as part of an arrest. Otherwise, authorities could use an arrest as an excuse to rummage through the suspect’s car, or home or workplace without bothering to consult a judge. As Justice Antonin Scalia wrote in a dissent for himself and three other justices, the Fourth Amendment was written precisely to prevent such “general warrant” searches used indiscriminately by the crown against Colonists.

Scalia concedes that DNA profiling has benefits, including leading to the conviction of the guilty and exonerating the innocent. But there is reason to be wary of the privacy implications of creating government databases of complete genetic profiles of American citizens who may not have committed any crimes. Otherwise, he said, every American would be subject to a DNA test when boarding an airplane, applying for a driver’s license or registering for school.

The questions raised by this case are not about the usefulness of DNA, but how it is used and by whom. This decision is likely not the last word on the question. As the court hears future DNA cases, it should not stretch the Constitution to allow any government searches without good cause.